Question

a given circle has an approximate area of 452.4 square units. How long is the circles radius?

Answer 1

Given:

Area of circle is 452.4

Find: Radius of circle.

Sol:.

Area of circle is:

$A=\pi r^2$

Area = 452.4

$\begin{gathered} A=\pi r^2 \\ 452.4=\pi r^2 \\ r^2=\frac{452.4}{\pi} \\ r^2\cong144 \\ r=\sqrt[]{144} \\ r=12 \end{gathered}$

So radius of circleis 12